selftests/landlock: Add tests for unknown access rights

Make sure that trying to use unknown access rights returns an error.

Cc: Shuah Khan <shuah@kernel.org>
Link: https://lore.kernel.org/r/20220506160820.524344-5-mic@digikod.net
Cc: stable@vger.kernel.org
Signed-off-by: Mickaël Salaün <mic@digikod.net>

tools/testing/selftests/landlock/fs_test.c

@@ -448,6 +448,22 @@ TEST_F_FORK(layout1, file_access_rights)
 	ASSERT_EQ(0, close(path_beneath.parent_fd));
 }
 
+TEST_F_FORK(layout1, unknown_access_rights)
+{
+	__u64 access_mask;
+
+	for (access_mask = 1ULL << 63; access_mask != ACCESS_LAST;
+	     access_mask >>= 1) {
+		struct landlock_ruleset_attr ruleset_attr = {
+			.handled_access_fs = access_mask,
+		};
+
+		ASSERT_EQ(-1, landlock_create_ruleset(&ruleset_attr,
+						      sizeof(ruleset_attr), 0));
+		ASSERT_EQ(EINVAL, errno);
+	}
+}
+
 static void add_path_beneath(struct __test_metadata *const _metadata,
 			     const int ruleset_fd, const __u64 allowed_access,
 			     const char *const path)